Locked tufting stitch



Dec. 28, 1965 A. J. CASSELLI 3,225,725

LOCKED TUFTING STITCH Filed Dec. 9, 1963 F g- 6 INVENTOR.

A. JOHN CASSELLI 33" BY WITNESS W0 QDQZ My. dud-d ATTORNEY United States Patent 3,225,725 LOCKED TUFTING STITCH Aveo John Casselli, Oakland, N.J., assignor to The Singer Company, New York, N.Y., a corporation of New Jersey Filed Dec. 9, 1963, Ser. No. 328,807 3 Claims. (Cl. 112410) This invention relates to the art of stitch formation, and more particularly, to a novel and improved stitch for forming and attaching loops or strands on the surface of a workpiece so as to provide what is referred to in the art as a tufted fabric.

It is an object of this invention to provide a stitched steam from which a series of loops or strands terminate free of concatenation and are thus suitable for the formation of a pile fabric.

It is also an object of this invention to provide a stitch suitable for the formation of a tufted fabric in which the loops or strands are locked securely to the workpiece by a simple but effective concatenation of the very thread of which the loops or strands are a part.

The above and additional objects and advantages of the present invention will be clear from the description which follows and the accompanying drawings of the stitched seam of this invention and several variants thereof in which:

FIG. 1 represents a top plan view of a workpiece having stitches formed therein in accordance with this invention,

FIG. 2 is a vertical cross-sectional view taken substantially along line 22 of FIGv 1,

FIG. 3 is a bottom plan view of the stitched workpiece of FIG. 1,

FIG. 4 is a bottom plan view of a stitched workpiece similar to that illustrated in FIG. 3 but with the tufted loops severed to provide single free ended strands,

FIG. 5 is a vertical cross-sectional view of a modified form of the stitched seam of FIG. 2 in which the locking loops are untwisted, and

FIG. 6 represents a bottom plan view of a workpiece having stitches formed as illustrated in FIG. 5.

Referring to FIGS. 1, 2, and 3, the stitched seam of this invention is illustrated as applied to a workpiece 11 which may be a single ply or super-posed plies of fabric, sheet material, or the like. FIGS. 1 and 3 illustrate the top and bottom plan views, respectively, of a fragment of three similar and parallel lines of stitching 20, 20 and 29 in the workpiece with the lines of stitching being formed from left to right as illustrated in these figures. Since the lines of stitching are similar, only the line of stitching 20 will be described and like portions in the other lines of stitching 20 and 20" will be indicated by like prime reference characters.

In FIGS. 1, 2, and 3, the successive points along the workpiece 11 at which a single continuous thread 30 is projected through the workpiece are indicated alternately by the reference characters 31 and 32. At alternate penetration points 31 a tufting loop 33 is formed through the workpiece and at alternate penetration points 32 a locking loop 34 is formed in the thread.

Each locking loop 34 is twisted one half turn about the axis of penetration of the locking loop, which axis is indicated by the line x-x in FIG. 2. The preceding tufting loop 33 is passed through each twisted locking loop 34 and beyond the passed through locking loop, each tufting loop 33 is free of further concatenation.

The tufting loops 33 are extended beyond the passed through locking loops and maintained extended to a length substantially greater than the distance between the point 32 at which the locking loop 34 is projected through the workpiece and the point 31 at which the next succeeding tufting loop 33 is projected through the workpiece. The locking loop 34 for each stitch is set into the workpiece after the preceding tufting loop has been passed therethrough and this setting of the locking loop secures the tufting loop in place, since further tension applied along the continuous single thread will tighten the locking loop about the tufting loop before it will continue back along the thread to cause reeving of the tufting loop relatively to the locking loop.

The length of each tufting loop is, therefore, effectively fixed as of its condition at the time the corresponding locking loop through which that tufting loop passes is set into the workpiece. Control of pile height or pile density, therefore, is simply a matter of controlling the degree to which the tufted loops 33 are maintained extended when a the corresponding locking loops 34 are set into the workpiece.

The distance between work penetration 31 and 32 may be made equal, or as illustrated in FIGS. 1, 2, and 3, each point 32 of penetration of the locking loops 34 may be located substantially nearer to the next preceding point of penetration 31 of the tufting loop than to the point at which the next succeeding tufting loop is projected through the workpiece. This arrangement provides for a more secure locking of the tufting loops in the workpiece.

FIG. 4 illustrates a modification of the seam illustrated in FIGS. 1, 2, and 3 in that each tufting loop 33 has been severed at a point beyond the locking loop 34 through which said tufting loop passes. FIG. 4 illustrates severance of the tufting loops 33 at the extreme free end of each tufting loop to provide substantially equal length strands 43 and 44. Preferably severance of the tufting loops 33 is deferred until after the tufting loop has been secured to the workpiece by the setting of the corresponding locking loop 34.

FIGS. 5 and 6 illustrate yet another modification of the stitch seam of this invention in which the locking loops 54 through which the tufting loops 33 are passed are not twisted prior to the passage therethrough of the tufting loops as are the twisted locking loops 34 in FIGS. 1 to 4. In all other respects the resulting seam and pile fabric illustrated in FIGS. 5 and 6 is identical to that previously described, including, as illustrated in FIG. 6, the fact that the tufting loops 33 may remain as loops or may be severed to provide separate strands 43 and 44.

Having thus described the invention, what I claim here- 1. A stitched seam in a workpiece comprising a single thread formed into a succession of loops, each loop projecting through said workpiece from one side thereof, each alternate one of said succession of loops being a tufting loop, each loop of said succession of loops between said tufting loops being a locking loop, said tufting loops being passed each through the next succeeding locking loop and thereafter extended beyond said passed through locking loop to a length substantially greater than the distance between the points at which said locking loop and the next succeeding tufting loop are projected through the workpiece, each of said locking loops being twisted one half turn about the axis of penetration of said locking loop through the workpiece and before said preceding tufting loop is passed therethrough, said locking loops each being set into said workpiece while said tufting loop passed therethrough is maintained extended, said tufting loops each being maintained free of concatenation with any succeeding tufting loops and each of said locking loops being projected through the workpiece at a point nearer to the point at which the next preceding tufting loop is projected through the workpiece than to the point at which 3 the next succeeding tufting loop is projected through the workpiece.

2. A stitched sea-m as set forth in claim 1 in which each of said tufting loops is severed at a point beyond the locking loop through which said tufting loop passes.

3. A tufted fabric comprising a workpiece, a plurality of parallel lines of stitches formed therein, each one of said parallel lines of stitches comprising, a single thread formed into a succession of loops, each loop projecting through said workpiece from one side thereof, each alternate one of said succession of loops being a tufting loop, each loop of said succession of loops between said tufting loops being a locking loop, said tufting loops being passed each through the next succeeding locking loop and thereafter extended beyond said passed through locking loop to a length substantially greater than the distance between the points at which said locking loop and the next succeeding tufting loop are projected through the workpiece, each of said locking loops being twisted one half turn about the axis of penetration of said locking loop through the workpiece and before said preceding tufting loop is passed therethrough, said locking loops each being set into said workpiece while said tufting loop passed therethrough is maintained extended and said tufting loops each being maintained free of concatenation with other tufting loops of any of said parallel lines of stitches and with any succeeding tufting loops.

References Cited by the Examiner UNITED STATES PATENTS 10,597 2/1854 Johnson 1l2262 13,687 10/1855 Singer 112-227 379,402 3/1888 Lamb et a1 112-262 X 1,260,517 3/1918 Currier 1l2265 X 1,827,614 10/1931 Riviere 112-266 X FOREIGN PATENTS 597,523 8/ 1925 France.

JORDAN FRANKLIN, Primary Examiner.

0 R. J. SCANLAN, Assistant Examiner. 

1. A STITCHED SEAM IN A WORKPIECE COMPRISING A SINGLE THREAD FORMED INTO A SUCCESSION OF LOOPS, EACH LOOP PROJECTING THROUGH SAID WORKPIECE FROM ONE SIDE THEREOF, EACH ALTERNATE ONE OF SAID SUCCESSION OF LOOPS BEING A TUFTING LOOP, EACH LOOP OF SAID SUCCESSION OF LOOPS BETWEEN SAID TUFTING LOOPS BEING A LOCKING LOOP, SAID TUFTING LOOPS BEING PASSED EACH THROUGH THE NEXT SUCCEEDING LOCKING LOOP AND THEREAFTER EXTENDED BEYOND SAID PASSED THROUGH LOCKING LOOP TO A LENGTH SUBSTANTIALLY GREATER THAN THE DISTANCE BETWEEN THE POINTS AT WHICH SAID LOCKING LOOP AND THE NEXT SUCCEEDING TUFTING LOOP ARE PROJECTED THROUGH THE WORKPIECE, EACH OF SAID LOCKING LOOPS BEING TWISTED ONE HALF TURN ABOUT THE AXIS OF PENETRATING OF SAID LOCKING LOOP THROUGH THE WORKPIECE AND BEFORE SAID PRECEDING TUFTING LOOP IS PASSED THERETHROUGH, SAID LOCKING LOOPS EACH BEING SET INTO SAID WORKPIECE WHILE SAID TUFTING LOOP PASSED THERETHROUGH IS MAINTAINED EXTENDED, SAID TUFTING LOOPS EACH BEING MAINTAINED FREE OF CONCATENATION WITH ANY SUCCEEDING TUFTING LOOPS AND EACH OF SAID LOCKING LOOPS BEING PROJECTED THROUGH THE WORKPIECE AT A POINT NEARER TO THE POINT AT WHICH THE NEXT PRECEEDING TUFTING LOOP IS PROJECTED THROUGH THE WORKPIECE THAN TO THE POINT AT WHICH THE NEXT SUCCEEDING TUFTING LOOP IS PROJECTED THROUGH THE WORKPIECE. 